1. Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland.
2. Department of Chemistry, Texas Christian University, Fort Worth, Texas.
3. Nanotechnology Characterization Laboratory, Leidos Biomedical Research, Inc., Frederick, Maryland.
4. Nanotechnology Core Facility, Office of Scientific Coordination, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas.
5. FDA Commissioner's Fellowship Program, Office of Chief Scientist, Office of the Commissioner, Silver Spring, Maryland.